This book excels at showing the inner workings and issues involved in designing custom COM-based components in VB, ATL, and/or MFC, as well as tapping the built-in components that come standard with COM, including transactions, mail objects (with CDO), and database programming (with ADO). In particular, for the C /ATL/MFC developer, practical sources of information (and sample code) are in short supply, and for this readership, the book fills a particularly worthwhile niche. Much of it uses VB in examples for designing effective, high-performance components.